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I'm currently reading (Re-reading actually) Cosmos by Carl Sagan, and in a chapter where he talked about Venus and how hot Venus is (Venus is actually the hottest planet in the solar system despite Mercury being closer to the Sun - although this wasn't mentioned in the book), and how the space probes that were sent there met an ugly fate, he had this interesting footnote which I want to share -

"In this stifling landscape, there is not likely to be anything alive, even creatures very different from us. Organic and other conceivable biological molecules would simply fall to pieces. But, as an indulgence, let us imagine that intelligent life once evolved on such a planet. Would it then invent science? The development of science on Earth was spurred fundamentally by observations of the regularities of the stars and planets. But Venus is completely cloud-covered. The night is pleasingly long - about 59 Earth days long but nothing of the astronomical universe would be visible if you looked up into the night sky of Venus. Even the Sun would be invisible in the daytime; its light would be scattered and diffused over the whole sky - just as scuba divers see only a uniform enveloping radiance beneath the sea. If a radio telescope were built on Venus, it could detect the Sun, the Earth and other distant objects. If astrophysics developed, the existence of stars could eventually be deduced from the principles of physics, but they would be theoretical constructs only. I sometimes wonder what their reaction would be if intelligent beings on Venus one day learned to fly, to sail in the dense air, to penetrate the mysterious cloud veil 45 kilometers above them and eventually to emerge out the top of the clouds, to look up and for the first time witness that glorious universe of Sun and planets and stars."

. . .

Carl Sagan is an amazing author, and I've shared the famous excerpt from his book Pale Blue Dot multiple times before - https://news.ycombinator.com/item?id=47565381

A few mentions of his books in my blog post here - https://www.rxjourney.net/30-things-i-know

I'll shamelessly resurface a comment I made a few years back.

There's a school of thought which views Venus as a better colonization candidate than Mars, and as early as the 70's scientists envisioned floating cities. From https://en.wikipedia.org/wiki/Colonization_of_Venus:

In effect, a balloon full of human-breathable air would sustain itself and extra weight (such as a colony) in midair. At an altitude of 50 kilometres (31 mi) above the Venusian surface, the environment is the most Earth-like in the Solar System beyond Earth itself – a pressure of approximately 1 atm or 1000 hPa and temperatures in the 0 to 50 °C (273 to 323 K; 32 to 122 °F) range. Protection against cosmic radiation would be provided by the atmosphere above, with shielding mass equivalent to Earth's.

Being able to wear a simple breathing mask while working outside instead of a full pressure suit is a boon. Of course high windspeeds and the constant bombardment of acid rain would be a problem.

I could imagine Venus one day being an exotic, cloud-top paradise for the rich (reminiscent of BioShock Infinity) that's expensive to maintain, and Mars a brute workhorse that eventually displaces it as a more resilient habitat over the very long term (eg. after terraforming).

There was this project idea that some researchers at Langley developed in the mid-2010s called HAVOC (High Altitude Venus Operational Concept) [0] for a 5-stage mission to send humans to Venus's habitable-ish cloud layers. It never really got anywhere, but there was apparently some media attention around it for some time.

Because the nitrox atmosphere we're used to is a lifting gas in the Venusian atmosphere, you could theoretically just fill a big balloon with our atmosphere and live inside it, with lots of Teflon on the outside and suits made of Teflon to work outside the habitat. I also (kind of?) remember reading about using metal nets to capture and condense H2SO4 from the clouds and process it into water, oxygen, and hydrolox rocket fuel.

[0] https://ntrs.nasa.gov/api/citations/20160006329/downloads/20...

"Even the gravity on Venus (0.91g) is homelike, which means that airship habitats, sensors, smoke detectors, toilets, and all the rest can be developed on Earth instead of forcing us to build a space station that can simulate Martian gravity."

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Imagine living on an airship high above the Earth, with the hard rule that you can never land. You must be entirely self-sufficient save for a tiny amount of material delivered infrequently. Now imagine trying to land on that airship from orbit or get back into orbit (and beyond) from that airship. None of this is easy here on Earth.

A mission that merely orbited Venus and returned without attempting to muck about with airships might be an intermediate step on the way to Mars. Trying to get closer to the surface than orbit would make things a lot harder.

Colonization of Venus, Geoffrey A. Landis, NASA Glenn Research Center, 2003

https://ntrs.nasa.gov/api/citations/20030022668/downloads/20...

The average lifetime of probes landing on Venus counting in minutes might have something to do with that?

"So that’s the bad part. But once you move past it, you start to notice that everything gets easier on Venus."

If wishes were fishes ...

> Missions to the clouds of Venus are either going to find life or some kind of brand new chemistry, either of which will be a breakthrough discovery in planetary science. There’s basically a guaranteed Nobel prize waiting in the skies of Venus for whoever wants to collect it.

why dont they send a probe to scoop up some venus air and bring it back? seems much easier than going with humans around the moon

Kurzgesagt's Venus video:

https://m.youtube.com/watch?v=G-WO-z-QuWI

> The phosphine detection was controversial when it was first announced in 2022, but it has since been corroborated by multiple measurements.

I thought it was resolved as SO2, not phosphine

Because, to be honest, whats the point? We can pretty much determine the composition of the atmosphere with spectroscopy, and we can't land without being crushed, boiled and dissolved at the same time. If we go to Mars, we can potentially find things on the surface (eg interesting geological formations) much faster than a rover could, and potentially run more in-depth scientific tests on what we do find, rather than just what we can send on a single rover

Why not the Sun?

The biggest problem is it's spin rate: a Venus day is 116 days Earth days or so.

Being completely tidally locked would be better because near the transition zones the permanent sun would make solar power and plants quite productive.

But an ecosystem where the planet spends most of the year in darkness or dim light?

Basically it's relatively easy to redirect comets to provide gas and liquids for the surface of Mars: that's technically demonstrated technology now.

There's almost no plausible way we could add momentum to Venus to give it a more reasonable day night cycle (I have seen some suggestion that shearing asteroids into it might be possible, but just the magnitude of momentum you're trying to add is staggering).

Venus is in what I call the thermolocks zone, not the goldilocks zone. The thermolocks zone is optimal for solar power and perhaps therefore for computation, although heatsink radiators are essential.

The atmosphere of Venus in particular is very resource rich, and so it would be incredible to mine it for heavy use by a space economy. This mining is supposed to use free solar power. All of this is a job for robots, not humans.

Why not Zoidberg?